Protected branches system (#339)

* Protected branches system

* Moved default branch to branches section (`:org/:reponame/settings/branches`).
* Initial support Protected Branch.
  - Admin does not restrict
  - Owner not to limit
  - To write permission restrictions

* reformat tmpl

* finished the UI and add/delete protected branch response

* remove unused comment

* indent all the template files and remove ru translations since we use crowdin

* fix the push bug

models/migrations/v17.go

@@ -0,0 +1,29 @@
+// Copyright 2016 Gitea. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/go-xorm/xorm"
+)
+
+func setProtectedBranchUpdatedWithCreated(x *xorm.Engine) (err error) {
+	type ProtectedBranch struct {
+		ID          int64  `xorm:"pk autoincr"`
+		RepoID      int64  `xorm:"UNIQUE(s)"`
+		BranchName  string `xorm:"UNIQUE(s)"`
+		CanPush     bool
+		Created     time.Time `xorm:"-"`
+		CreatedUnix int64
+		Updated     time.Time `xorm:"-"`
+		UpdatedUnix int64
+	}
+	if err = x.Sync2(new(ProtectedBranch)); err != nil {
+		return fmt.Errorf("Sync2: %v", err)
+	}
+	return nil
+}